1. Technical Field
This disclosure is directed to a deodorant and air sanitizing aerosol spray composition in combination with a spray valve and spray performance parameters to provide optimum dispersion of the composition into the surrounding air.
2. Description of the Related Art
Various compositions are available to mask malodors in the air. Additionally, various compositions are available to sanitize and remove malodors from the air. These compositions may be dispensed by various spray devices including aerosol dispensers.
Aerosol dispensers have been commonly used to dispense personal, household, industrial, and medical products, and to provide a low cost, easy to use method of dispensing a liquid product. Typically, aerosol dispensers include a container, which contains a liquid product to be dispensed. A propellant is used to discharge the liquid from the container. The propellant, which may be a mixture, typically has a boiling point slightly below room temperature so that, under pressure, the propellant exists as equilibrium between a vapor phase and a liquid phase. The vapor phase of the propellant provides sufficient force to expel the liquid product from the container when a user actuates a discharge valve by, for example, pressing an actuator button. When the valve is closed and the container is resealed, the vapor phase of the propellant is replenished by the liquid phase as the equilibrium between the vapor and liquid phases is reestablished within the container.
As illustrated in FIG. 3, a conventional aerosol dispenser generally comprises a container (not shown) for holding a liquid product and a propellant, and a valve assembly 104 for selectively dispensing a liquid product from the container. The valve assembly 104 comprises a mounting cup 106, a mounting gasket 108, a valve body 110, a valve stem 112, a stem gasket 114, an actuator cap 116, and a return spring 118. The valve stem 112, stem gasket 114, and return spring 118 are disposed within the valve body 110 and are movable relative to the valve body 110 to selectively control dispensing of the liquid product. The valve body 110 is affixed to the underside of the mounting cup 106, such that the valve stem 112 extends through, and projects outwardly from, the mounting cup 106. The actuator cap 116 is fitted onto the outwardly projecting portion of the valve stem 112 and is provided with an actuator orifice 132. The actuator orifice 132 directs the spray of the liquid product into the desired spray pattern. A dip tube 120 is attached to the lower portion of the valve body 110 to supply the liquid product to the valve assembly 104 to be dispensed. The whole valve assembly 104 is sealed to a container by the mounting gasket 108.
In operation, when the actuator cap 116 of a dispenser is depressed, the propellant forces the liquid product up the dip tube 120 and into the valve body 110 via a body orifice 122. In the valve body 110, the liquid product may be mixed with additional propellant supplied to the valve body 110 through a vapor tap 124. The vapor tap 124 helps to mix the liquid product and propellant in the valve body 110, to thereby break up the product into smaller particles suitable to be dispensed. From the valve body 110, the product is propelled through a stem orifice 126, out the valve stem 112, and through an actuator orifice 132 formed in the actuator cap 116.
One propellant used to propel liquid product from an aerosol container using the valve assembly 104 of FIG. 3 may be a B-Series propellant having a propellant pressure of 40 psig (B-40), at 70° F. (2.722 atm at 294.261 K). “Propellant pressure” refers to the approximate vapor pressure of the propellant, as opposed to “can pressure,” which refers to the initial gauge pressure contained within a full aerosol container. In order to effectively dispense liquid product, the valve assembly may have a stem orifice diameter of 2×0.020″ (2×0.0.508 mm), i.e., two holes of 0.020″ diameter, a vapor tap diameter of 0.020″ (0.508 mm), a body orifice diameter of 0.062″ (1.575 mm), and a dip tube inner diameter of 0.060″ (1.524 mm). One currently known aerosol air sanitizer contains hydrocarbon propellant in the amount of approximately 29.5 wt % of the contents of the dispenser assembly along with 6-8.8 wt % of glycol and pure alcohol solvent with no water present.
Hydrocarbon propellants are considered to be Volatile Organic Compounds (VOCs). The content of VOCs in aerosol air sanitizers has the potential to be regulated by federal and/or state regulatory agencies, such as the Environmental Protection Agency (EPA) and California Air Resource Board (CARB).
One way to reduce the VOC content in such aerosol air sanitizers is to reduce the content of the hydrocarbon propellant used to dispense the liquid product. However, a reduction in the propellant content can adversely affect the product performance. Specifically, reducing the propellant content in the aerosol air sanitizer may result in excessive product remaining in the container at the end of the life of the dispenser assembly (product retention) and an increase in the size of particles of the dispensed product (increased particle size). It is desirable to minimize the particle size of a dispensed product in order to maximize the dispersion of the particles in the air and to prevent the particles from “raining” or “falling out” of the air. Thus, an aerosol dispenser assembly that can satisfactorily dispense an aerosol product should include a desirable level of propellant to provide high quality product performance throughout the life of the dispenser assembly.
The “life of the dispenser assembly” is defined in terms of the pressure within the container (i.e., the can pressure), such that the life of the dispenser assembly is the period between when the pressure in the container is at its initial pressure (typically a maximum) and when the pressure within the container is substantially depleted, i.e., equal to atmospheric pressure.
The use of the terms “sanitizing” and “disinfecting” herein is consistent with Environmental Protection Agency Disinfectant Technical Science Section (DIS-TSS) nos. 01, 08, 11 and 13 (http://www.epa.gov/oppad001/sciencepolicy.htm). For example, in regard to hard surface cleaning products, DIS-TSS-01 requires a product labeled as a “disinfectant” to be tested with sixty carriers, each with three different samples (for a total of 180 samples), representing three different batches, one of which is at least 60 days old, against Salmonella choleraesuis (ATCC 10708—Gram negative) or Staphylococcus aureus (ATCC 6538—Gram positive). Under DIS-TSS-01, to support a label claim of the product being a “disinfectant,” the product must provide a complete kill 59 of 60 carriers at a 95% confidence level. Thus, under DIS-TSS-01, a complete kill is essentially required for label claims of effectiveness as a “general disinfectant” or representations that the product is effective against a broad spectrum of microorganisms, including Gram-positive and Gram-negative bacteria.
In contrast to “disinfecting” and the requirements of DIS-TSS-01, which refer to a complete kill of all bacteria on a test (hard) surface, the term “sanitizing” refers to a less than complete kill of the bacteria in air. EPA regulations currently prohibit label claims of “disinfectant” on sanitizing products used in air that reduce airborne bacteria but nonetheless do not provide a complete kill of all bacteria in air. In fact, the EPA imposes separate requirements for the label use of “sanitizing” for air (DIS-TSS-11).
DIS/TSS-11 applies to products with label claims of reducing airborne microorganisms or bacteria. Glycol vapors have been shown to produce significant decreases in numbers of viable airborne bacteria within enclosed spaces. Aerosol formulations including glycols (triethylene, dipropylene, or propylene glycol) at concentrations of 5% or more will temporarily reduce numbers of airborne bacteria when adequate amounts are dispensed within a room. Unlike DIS-TSS-01, no specific standards or methods for evaluating air sanitizers have been adopted and incorporated into DIS-TSS-11.
Thus, it has been known to use certain glycols in aerosols compositions to sanitize the air in a room by decreasing the presence of airborne bacteria that are often a source of malodors. One particular glycol, triethylene glycol (“TEG”), has been found particularly effective for sanitizing air when delivered via an aerosol spray. The commercially successful OUST® air sanitizer products utilize a mixture that contains about 6 wt % of TEG. TEG has also been used as an air treatment for tobacco smoke.
There is a need for an improved aerosol composition and aerosol dispenser whereby the aerosol composition effectively controls airborne microorganisms and malodors and has a low total VOC content and whereby the aerosol dispenser delivers the composition to the ambient air with a desired particle size and spray rate to improve the air sanitization performance.